I'm not sure if this is only happening to me, or it's a systemwide-issue, but I've only seen it for a day or so and already I'm going a bit nuts:

Seemingly in an effort to make the full page visible below the new JiveWorks banner, it seems like the main body content is pushed down on the page by the height of the banner. However, the moment I scroll down by even a pixel, either an artificial spacer is removed or the body content is dropped into a layer behind the banner, causing it to jump upward, leaving the top inch or so hiding behind the banner. Scrolling further behaves as expected, and scrolling back up is normal until the edge is reached, at which point the content jumps again to sit below the banner. This jumpy movement is frustrating enough, but it also seems to be implemented as a periodic javascript trigger, as the repositioning happens a moment or two after the edge is reached.

I'm in Safari 10.0.1 on macOS 10.12.1. I haven't been able to check other browser/OS combinations.